It is well known that light has a tremendous effect on the health of humans. Several diseases are attributed to deficiencies in the exposure of humans to natural light. They can be successfully treated with a light therapy, in the course of which a person is exposed to light emitted by a therapy light source. Light therapy can involve the treatment of different areas of a patient's skin with light of a particular wavelength and intensity. In particular, blue light in a wavelength range between approximately 445 to 480 nm (nanometer) is known to suppress melatonin and affect the internal clock of the body and accordingly the circadian rhythm. It is thus well suited for a treatment of patients with circadian rhythm disorders in particular and, more generally, for patients with sleep disorders, jetlag, depressions and seasonal affective disorder. For providing light radiation suitable for light therapy purposes, therapy light sources and control devices are available for light therapy purposes.
Documents US 2008/0091250 A1 discloses a light therapy desk lamp as a light source for therapy purposes that can be easily used at home. In one embodiment, the disclosed light therapy desk lamp includes a controller for manually setting light therapy parameters, like selecting the wavelength, the intensity and the duration of a therapy. In another embodiment, a user provides conditions or symptoms of a disorder as in input to the controller and the controller receives parameters for a treatment from internal database. In yet another embodiment, a user can provide operating parameters in accordance with a customized therapy program.
A drawback of known light therapy systems is that the treatment is either not adapted to a patient's need, or that customization has to be provided manually, which might be problematic, in particular if the therapy is not supervised by a medical professional.
It would thus be desirable to provide a lighting system for light therapy purposes and a control device for controlling a therapy light source that automatically adapts a light therapy to the needs of a patient.